Luis drescher



' (No Model.) /1

L. DRE'SOHER. I

MEDICAL INDUCTION COIL. No. 352,084. Patented Nev n "2, 1886,

V N. PETERS, Phnm-Lnhu m her. Washingvm, D4 C4 UNITED STATES PATENT OFFICE.

LUIS DRESCHER, OF NEW YORK, N. Y.

MEDICAL INDUCTION-COIL.

SPECIFICATION forming part of Letters Patent No. 352,084, dated November 2, 1886. Application filed November 21, 1885. Serial No. 183,483. (No model.)

To alt whom it may concern:

Be it known that l, LUls DRESOHER, of the city, county, and State of New York, have invented a new and useful Improvement in Medical Induction-Coils; and 1 do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, making apart of this specification.

My invention relates to an improved con struction of portable or pocket electromagnetic machines, and has for its object to furnish at a reduced cost of manufacture a more powerful and efficient instrument within a given compass than those heretofore eon-- structed, and which, by a combination of electrodes directly with its case, will facilitate local applications of the electric current.

In the accompanying drawings, Figure 1 is a plan View of the upper side of one of my improved pocket electromagnetic machines, full size; Fig. 2, a similar view of the under side thereof, with the electrodes attached thereto, one of said electrodes being partly cutaway to bring a metallic connection-piece in sight; Fig. 3, an elevation of one end of the instrument, showing its induction-coil; Fig. 4, an elevation of its opposite end, illustrating the arrangement of its battery-cells. Fig. 5 furnishes a bottom 'or plan view, and also a longitudinal section, of one of the electrodes detached; Fig. 6, an enlarged longitudinal section of the instrument complete, in line a: mot Fig. 7 5 and Fig. 7, an enlarged longitudinal section taken centrally through the thickness of the case in line 111g of Fig. 6.

A represents the case for my instrument, preferably made of hard rubber, and constructed with two cylindrical recesses, B B, at one end to receive the battery-cells,and with a compartment, D, extending across its opposite end to receive the induotorium of the ap paratus.

The inductorium is constructed of a horseshoe-magnet, one of whose arms is fixed and rigid and serves as the core for the inductioncoil, while its other arm is made elastic, so as to be free to vibrate to and from the first. The

fixed arm or core is formed of a metallic rod, d, Figs. 6 and 7, encircled by a helical coil, 0,

of sheet-iron, closely wrapped thereon longitudinally, and over which is wound the induotion-coil e, of insulated wire. This inductioncoil is inclosed within a case or cylindrical shell, E, ot'hard rubber, upon which is wound spirally a single da'mpencoil, g. A heavy iron disk, Z, of a diameter equal to that of the end of the case E, is riveted to the end of the central core-rod, d, and constitutes one pole of the magnet. The other end of said core-rod is threaded, and one end of an elastic strip of iron, M, is made fast thereto by means of a nut, d, screwing upon the rod, said iron strip being bent around the case E and extended parallel-with the core 0 out to the edge of the disk Z, as shown in Fig. 7. The nut d also serves to connect and combine the inner end of the wire of the inductioncoil .e to said strip M. This iron strip M is widened as it approaches the disk Z, and curved transversely, so as to cover and embrace a considerable portion or the induction-coil. ,lt is sufiiciently elastic to admit of free vibration, and its outer end is doubled, so as to concentrate a greater mass of iron at its extremity opposite the edge of the disk Z. [this heavy end of the vibrating strip constitutes the opposite pole of the electro-magnet, and, being strongly attracted to the fixed pole or disk Z whenever the mag net is excitcd, operates as an extremely sensitive armature.

to fit closely into the compartment D of the case. Upon this base-board Q a thin metallever, whose shorter arm P is bent up from the base, to serve as a contact-point opposite the side of said armature M, near its inner end. i The end of this upright arm P of the lever is fitted with platinum, and a platinum piece is likewise secured upon the side of the armature M opposite thereto, (see Fig. 6,) so as to insure an electrical connection between the two when they come into contact with each other.

The longer arm of the lover I? is carried parallel with theinduction-coil out through a narrow slot in the side of the case, and terminates in a small button, 1?. By swinging this longer outer arm to the one side or the other the The induction-coil, with its armature, is secured to a thin board, Q. adapted .85 he strip, P, is pivoted outside of the vibrat ing armature M of themiagnet, to serve asfa platinum point on its shorter inner arm, 1?, is-

made to approach more or less closely the armature M. The extreme length of this outer arm, as compared with that of the inner arm, permits an extremely delicate adjustment of the contact-point P upon the latter to and from the armature. The longer arm of the lever is made to rest and move upon a metallic plate, \V, which is confined by means of a screw, \V, inserted from the outer under face of the case through a metallic strip, a, thereon. A second plate, V, is also fitted upon the opposite end of the base-plate Q, and is secured in like manner by a screw, V, inserted from the outer under side of the case through a metallic contact-plate, V, thereon. This second plate, V, is connected by means of a short wire with the core-rod d, and thereby with the inner end of the wire of the induction-coil 6, being confined by the nut cl at the end of the rod.

The open end of the compartment D is preferably closed by a glass plate, S, whereby the rheotome and induction-coil are exposed to view. A damper plate or strip, L, is fitted transversely upon the outside of the case over the compartment D, (see Figs. 1 and 6,) to extend longitudinally centrally over the induction-coil. This strip is made fast to the edge of the case at either end, and covers a narrow longitudinal slot cut through the case. A slide, K, Figs. 1, 3, and 6, is fitted to move along the strip, and from it a finger, K, Fig.

6, depends through the slot, to extend laterally within the case over the damper-coil g and in contact therewith. One end of said damper-coil g is connected with the strip L, and by the movement thereon of the slide K one or more of the convolutions of the dampercoil are closed by the finger K in an independent circuit encircling the primary coil 6, and which, beginning at the end of the finger K, passes through the damper-coil g to the end thereof, which is connected to the strip L, and thence along said strip to the slide K and finger K. The induced current produced in this independent circuit will operate as an equivalent i'or that which would be produced in a metallic tube passed over the induction-coil to the same distance in neutralizing the effect of the induction coil.

At the bottom of each cylindrical recess B B in the case A a metallic conducting-strip is centrally fitted. One of said strips, a, is made to extend from the recess B to the outer under face of the case, and over it to the screw W, which fastens the bearing-plate W under the lever P, so that a continuous electrical connection is formed thereby from the bottom of the cell-receptacle B to the lever P. The strip a at the bottom of the cell-receptacle B is made to extend out to the side of the case adjacent thereto, and the outer end of the wire 6 of the inductioncoil is secured thereto by a screw, see Fig. 6,) so that the bottom of said cell-receptacle is placed in connection with the coil, and through the coil with the vibrating armature M of the rheotome, and also with the plate V and the screw V, retaining said plate.

The heads of the screws \V' and V on the under side of the case are enlarged to form buttons, (see Fig. 6,) and similar buttonheaded screws are inserted at the opposite end of the case at the same distance from its sides, the four screws serving thereby as fasteners for the fixed electrodes T T of the instrument. These electrodes consist each of a metal strip, B, (see Fig. 5,) of a length corresponding to that of the case A, provided at either end with an aperture to fit over the heads of the screws, and a slot extending in the same direction from each aperture to admit of sliding the strip in that direction until the wide heads of the screws overlap the slots, and thus confine the strip upon the case. A thin narrow plate, R, (see Fig. 5,) is secured centrally upon the outer face of each electrode-strip to extend over each of the slotted apertures therein, so that the heads of the screws shall come into contact with the plate when the strip is secured in place upon the case. This outer strip thus not only insures contact between the strip and screws, but at the same time protects the facing of the strip from being caught by the screw-heads. The facing of the electrode consists ofalining, T, ofsponge, fiannel, felt, or other absorbent material, which completely covers the outer face of the metallic strip R and is made fast thereto along its edges.

The battery-cells C O are constructed of cylindrical vessels, preferably of hard rubber or glass, open at both ends and closed by step pers F F', of rubber or other elastic material. For the sake of economy and to insure more fully a tight joint, one end is preferably contracted to receive a small stopper, F, and to this small stopper a rod, G, of zinc is centrally secured, to project inwardly therefrom. (See Fig. 6.) The second large stopper, F, is secured to a carbon cup or cylinder, H, made to project inwardly therefrom, so as to encircle concentrically, when inserted in the c all, the rod ofzinc G, projecting from the opposit-e stopper. Each stopper is fitted exteriorly with a central button, f, which is connected by a suitable wire with the element carried by the stopper.

The recesses B B, containing the cells, are closed and the cells C O secured therein by a metallic cap-plate, I, fitting upon the end of the case to bear against the metallic buttons ff of the outer stoppers of the cells, so as to form an electrical connection between them. This cap-plate is secured by a rotating catch or thumb-plate, t, pivoted to the body of the ,case between the recesses, and whose head,

passing through a narrow central slot in the capplate, secures it by being turned at a right angle thereto, so as to overlap the edges of the slot. \Vhen the thuinb-platet is turned parallel with the slot to permit of a withdrawal of the plate I, its ends will overlap the edges of the cells, so as to keep the cells from dropping out after the cap-plate is removed. The cells may then be withdrawn by turning the thumb-plate once more into a transverse posi tion.

ln inserting the battery cells into the case one of them is reversed, so that the connecting strip 1 will couple the negative element of the one cell with the positive element of the other. as shown in Fig. 2.

From the foregoing description of my improved Faradic instrument it will be seen that there are, two coils included therein-the one 0, which is wound on the fixed iron core (I of the U-shaped magnet, whose opposite elastic arm, M, constitutes the contact breaker of the rheotome, generating the induced current, and the other, 9, called the damper-coil, which is made'to encircle the coil 6, regulating the intensity of the current generated in A the first.

In the operation of the machine, when the arm P of the lever P is in contact with the arm M of the magnet 01 M, the current from the battery circulates around the core 01 from the positive pole of cell 0, through the strip a, into the coil 0, and out into the vibratii'ig arm M, through the rhcotome M P, into the lever P, and back to the cells C and C. This constitutes the generatingcurrent. As the elastic arm of the U-shaped magnet d M is parallel with and in close proximity to the opposite arm. serving as the core of the induc tion-coil, and the ends of its two poles are near each other, a mutual attraction results so soon asthis generating ou rrent passing through the generating-coil e excites the magnet, not only at the poles of the magnet, but along the entire length of its arms, so that the elastic arm M is thereby drawn toward the rigid arm d by the feeblest possible current, causing thereby a break in the circuit at I. At this moment the magnet is demagnetized, and the arm M swings back by its own elasticity and connects again with the arm P to close the circuit. A new attraction follows, and a vibration of the arm is thus produced, resulting in the rapid automatic make and break of the circuit, common in all rheotomes.

It is well known that when an iron core demagnetizes it induces a current inthe surrounding coil, and also that when an existing current in a coil is broken it induces likewise a current in the same coil. This induced current, called by physicists the extra current or the primary induced current, circulates in the coil in the same direction as the generatingcurrent derived from the cells. This extra current is of a higher orderi. e., it is of a higher potential than the generating-currentand consequently causes shocks when made to traverse the human body, the generating or direct battery-current being of so low a potential as that it produces no such physio logical effect.

When the two electrodes (anode and cathode) of the apparatus are applied to the human body, to form an electric connection between them, a circuit is formed for the primary induced or extra current, created as above, by reason of the connection of one electrode with one end of the generatingcoil 6 through the magnet d M, the inner pate V, and its connection to the arm d by a short wire, the screw V, and the plate V, and by reason of the connection of the other electrode with the lever L through the plates a and W and screw W. The extra current following this circuit will induce a shock in the portion ot' the body included between the electrodes TT at each make and break of the rheotomes at M P. Inasmuch as these shocks are of uniform intensity, and in many instances too strong, they may be dampened z'. 6., their intensity may be regulated to any desirable degree by means of the coil 9, wound over and along the generatioircoil 6, above described. This damper-coil g, which is made of uucovered wire and wound in one spiral, preferably in such manner as that its convolutions remain insulated one from the other, being attached at one end to the metal strip L, on which the movable slide K and finger K play, the contact of the finger K with the first convolution of its spiral will create a very short circuit, beginning at the end of the plate K, passing along the plate to the finger K, thence along so much of the coil as is included between the end of said finger and the end of the plate K at the starting-point. By moving the finger K to include a larger number of convolutions the length of the circuit is increased to cover a correspondingly'greater length of thefiinduction coil e, in which is generated the ex a current. Each extra current in the coil 6 will at the moment of its beginning induce, as is well known, an inversely flowing current (of a higher order) in the encircling coil 9, which will react upon and operate to deaden or dampen the potential effect ofthe extra cur rent which caused it to an extent measured by the number of convolutions of the spiral connected into a circuit by means of the finger K, as described.

The battery-cells are charged for use by fill- IIO ing them with a small quantity of sulphate of I13 mercury and water, and being charged and replaced in the case, the instrument is ready for use. The electrodes T T being moistened and applied to any portion of the body, the electrical circuit will be closed thereby through the portion included between them, and in View of their close proximity to each other, (see Fig. 2,) the instrument is specially adapted for local applications, which, by its use, may be made with one hand. By making fast the wires of ordinary detached electrodes to the retaining-buttons W V of the strips R R the battery may be employed, as are all others, for varied applications.

By constructing the induction-coil so that its core shall constitute one pole of a horseshoe magnet, whose opposite pole constitutes a vibrating armature for the rheotome, an exceedingly sensitive automatic contact-breaker is obtained, which will vibrate under the influence of a much weaker current than will the armature of an ordinary rheotome, while the induced current is also strengthened by the action of the armature as well as of the core. By dispensing with the necessity of electrode cords and wires and detachedelectrodes the instrument is rendered much more compact and convenient for nse,and the novel position and arrangement of the electrodes T T, attached to the case,qnalify the instrument for a Variety of useful local applications not as readily obtained with other instruments, and this without detracting whatever from its efficient use with electrodes to be attached thereto in the customary manner by conductingwires.

Although I have described the instrument as constructed with two cells, it may be made in yet smaller form with one cell, or, if desired, in larger form with three or more cells, the two cell battery being, however, snfiiciently powerful for all ordinary medical purposes.

I claim as my invention-- 1. The combination, with the inductioncoil and rheotome in a Faradic machine, of a U shaped eleetro magnet constructed with parallel arms, of which one is elastic, the rigid arm being encircled by the inductioncoil and the elastic arm made to extend parallel with the coil in proximity thereto, and to operate by its vibration as the contact breaker of the rheotome, substantially in the manner and for the purpose herein set forth.

2. The combination,withthe batterycell O, inductigh-coil E, and vibrating armature M of an electromagnetic machine, and with a me tallic adj listing-lever, P, carrying the contact point for its rheotome,of themetallic connecting-strip Q, fixed to the case of the machine to extend from beneath the leverP to one pole of said battery-cell, ametallic plate, \V, traversed by the lever, and a screw, \V, connecting the strip and plate and titted with a head to pro- 4 5 ject from the case and serve as a fastener for one end of an electrode, T, for the machine, substantially in the manner and for the purpose herein set forth.

3. The combination,with the battery indnet-ion-coil and rheotome in a Faradic machine, and with a case containing the same, of the detachable slotted metallic strips R It, a facing,

T, of absorbent material fitted exteriorly upon each,wide-headed pins or screws secured to the case to project slightly therefrom and engage the slots in said strips R R, and thereby form a detachable fastening for the same, and electrical conductors connecting severally said pins or screws for the one strip with the positive pole and those for the other strip with the nega tive pole of the battery, substantially in the manner and for the purpose herein described.

4. Thecombinatiomwith theinduction-coils in a Faradie machine, of a damper-coil encircling the induction-coil, and a metallic finger sliding over the damper coil in contact with its convolutionsupon a metallic conductor connected with one end of said damper-coil, whereby an independent metallic circuit of greater or less extent is closed around the inductioncoil, substantially in the manner and for the purpose herein set forth.

5. The case A for an electromagnetic machine, constructed in one piece having one or more cylindrical recesses, B B, for the batterycells at one endand atransverse compartment, D, for the induction-coil and rheotome at the other, in con'ibination with a transparent cover, S, closing said compartment D, and a metallic plate, I, closing the receptacles B B, all substantially in the manner and for the purpose herein set forth.

In testimony whereoflhave signed my name to this specification in the presence of two subscribing witnesses.

LUIS DRESCHER.

itnessesz J OHN A. ELLIs, A. B. Moons. 

